Catch A Falling Star

by Stephen J. Bespalko

[Ed. Note: This article won second place in the adult
article competition in the California Federation
of Mineralogical Societies in 1996.]

On October 3, 1996, a large fireball was seen over many parts
of the southwestern United States. The size of the meteor
appears to make this a very rare event, and offers club
members the opportunity to hunt for a piece of the meteor,
which is believed to have made it to the ground. Additionally,
there is an opportunity to help internationally renowned
scientists with their investigation of the meteor fall, along with
the possibility of winning a reward for finding a piece of the
meteorite. (Also, it wouldn't hurt to have a chunk of this baby
in your collection.)

Mark Boslough, of Sandia National Laboratories, and John
Wasson, of UCLA, have developed a hypothesis of what
happened. They suggest that the object first entered the earth's
atmosphere at about 8 p.m. MDT on October 3, 1996, east of
Las Cruces, New Mexico. The trajectory of the meteor was
roughly east-north-east from there, towards the Texas
Panhandle. While it descended at a shallow angle, it slowed and
aerodynamic forces began to break it apart. Fragments could be
seen falling from the main body of the meteor along the path
that the meteor followed.

Boslough and Wasson believe that the main meteor fragment
had sufficient momentum to carry it back into space, where it
circled the earth once before reentering the atmosphere over
California. Until fragments of the meteor are collected in both
California and Texas (or possibly New Mexico), they can't
prove that the two fireballs seen that night are part of the same
meteor; however, the likelihood of the two events being linked
is quite high, Boslough asserts. The fact that the two fireballs
were on such a similar path, the time between the events, and
the location of the two meteor falls all lead them to suspect
that the two events are linked.

Since I work at Sandia National Laboratories, I gave Dr.
Boslough a call to find out what new information had come to
light since the latest set of news articles on the meteor were
published in the papers. He told me they had just completed
the analysis of the seismic signals from the earthquake sensing
system in California. The fact that the instruments intended for
detecting earthquakes were able to record the sonic boom from
the (hypothesized) reentry of the meteor is an indication of how
large an event this was. Enough of the sensors picked up the
sonic boom to give scientists a very accurate indication of the
California trajectory. They believe that the bulk of the
meteorites fell just west of Little Lake, California, in and
around the China Lake Weapons Testing Area, and perhaps as
far east as the Panamint Valley.

Boslough believes that the meteor is not a metal meteorite. The
evidence collected so far leads him to believe that this is a
"stony" or chondrite meteorite. He suspects this because metal
meteors tend not to come apart in the air, while this one may
have blown apart twice. Pictures of this type of meteorite can
be found in
Rocks From Space
by O. Richard Norton, which I reviewed in the Lithosphere
[August/September 1994]. In particular, see Chapter 17,
"Hunting For Meteorites," which shows what stony meteorites
look like in the environment in which the fragments are
believed to have fallen in California.

Dr. Wasson is offering a reward for a piece of this meteorite,
and may be contacted at the following address: Dr. John
Wasson; UCLA, Institute of Geophysics; Los Angeles, CA
90095.

For those with Internet access, the email address for Boslough
is mboslo@sandia.gov. Wasson can be reached at
wasson@igpp.ucla.edu. They would like to hear from anyone
who saw the meteor, has video tapes or pictures showing the
meteor, or anyone believing they found a piece of the
meteorite.

The scientific interest in this meteor is based on the rarity of a
"capture and reentry" event, as this one appears to be. There
have been only a small number of similar events recorded. The
most recent event of this type was the well-publicized "Peekskill
Fireball" that occurred on October 9, 1992, in which a meteor
crashed into a car parked in a driveway in Peekskill, New York
-- thus the name. Prior to that, there was a fireball seen in
August 1972: The meteor was not captured by the Earth's
gravitational pull, but thrown into a new orbit after grazing the
atmosphere. Based on data that included a film taken by a
tourist in Grand Teton National Park, scientists believe that the
meteor could return next year on August 11.

If you find a piece of the recent meteor (or any meteorite, for
that matter), there are a few things you can do to help the
scientific inquiry. Boslough suggests that, even if you want to
keep the fragment, to document the location where the
meteorite was found as accurately as possible. They would
especially like pictures of the fragment before it is
moved, showing the fragment in relationship to its
surroundings. If you don't have a way to accurately determine
the location of the fragment (such as with a Global Positioning
System unit), simply mark the site and notify the scientists
mentioned above. Any information they receive of this nature
will greatly aid their work. Boslough indicates that he does not
believe that handling the fragments will damage them in any
way or diminish the information they can extract from an
examination. He said he would also be interested in knowing if
there are any obvious marks on the ground around the site
where the fragment(s) are found.

The preceding article was originally published in the November 1996
issue of Lithosphere, the official bulletin of the
Fallbrook [California] Gem and Mineral Society, Inc; Richard Busch
(Editor).

Permission to reproduce and distribute this material, in
whole or in part, for non-commercial purposes, is hereby granted
provided the sense or meaning of the material is not changed and
the author's notice of copyright is retained.

Last updated: 18 September 2002
http://geopress.rbnet.net/fallstar.htm